The Internet

The Internet is a network of computer networks based on the TCP/IP (Transmission Control Protocol/Internet Protocol) protocols. Starting as the U.S. Department of Defense s ARPAnet circa 1970, it has grown to be an almost wholly privatized, global resource connecting more than 11,000 networks with 2 million host machines and 20-25 million computer users in more than 90 countries. It is estimated that Internet traffic has been growing at about 15% per month recently. In the U.S., one-third of all business mail in the last 5 years traveled over telephone wires, including both elearonic mail and facsimile. 

More and more frequently, computational chemists transfer academic and public domain software via file transfer protocol (ftp) over Internet or other networks connected to Internet, such as Bitnet. Thanks to the speed and accuracy of this method of communication, an individual can receive or download software at essentially no cost. 

To use ftp, the user types the telnet site command on a networked computer to reach the server (site) with the desired files. At the ftp prompt, typing help obtains the ftp commands. Typically, the files that are available for sharing are in a public directory, such as pub/filename. Files have to be identified by their name unfortunately, it is not possible with ftp to inspect the contents of a file before it is transmitted. 

There are many Gopher sites around the world, mostly at universities and government laboratories. A few Gopher sites of particular interest to computational chemists include those at the Ohio Supercomputer Center maintained hy Dr. Jan K. Labanowski and colleagues (infomeister.osc.edu), at the American Chemical Society headquarters in Washington, DC (acsinfo.acs.org), and at Northern Illinois University maintained by Dr. Steven M. Bachrach (hackberry.chem.niu.edu). 

The most recent medium for obtaining information on the Internet is through the World Wide Web (WWW or simply Web). A sampling of Universal Resource Locations (URL) of WWW servers of particular interest to computa- 

The Internet is a worldwide public computer network. The Internet was originally founded by the U.S. Department of Defense in the 1970s using Transmission Control Protocol/Internet Protocol (TCP/IP) to connect computers and networks. Since the inception of Hyper Text Markup Language (HTML) in the early 1990s, the Internet evolved from a text-based communications platform to graphically interfaced Web pages. HTML fueled the development of the World Wide Web (WWW) into websites that would be publicly accessible, would be hosted via Internet-connected network servers, and would allow for other media files rather than mere text to be accessed. 

The public internet was so successful that large companies developed their own private networks of computers called intranets, which greatly reduced paperwork and speeded the design process. 

A typical address for an internet web site would be http// www.asu.edu. This is called a uniform resource locator (URL) and corresponds to the following English translation  

An e-mail address is the cyberspace equivalent of a conventional mailing address. It must be unique and expressed in what is called hypertext protocol (abbreviated http //). A typical address in hypertext protocol would be  

C = the nature of the location (edu for educational institution in this case) 

If the location is not in the United States, the country must also be indicated at the end of the address. For example  

In the first edition of this book I wrote, A major use of the Internet is for electronic mail, but extremely rapid growth is being observed in other areas, particularly the World-Wide Web (WWW).. Such a phrase seems an understatement despite the hype, the Internet has certainly made a dramatic impact, not least on the scientific community, where its 

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Also a very important the instrument may be adapted to a customer s needs by only changing software, and handing a floppy disk to the customer. Even better, the customer himself can download the software from our server, using a modem or the Internet. 

The NDT Newsgroup and other forums are playing an important role in expediting meeting and communieation among your NDT colleagues on the Internet - Email is the most important tool for that. Not only technical discussions but also business to business or even direct inquiries are today handled via the Internet. Statistics are presented with more information on specific usage. 

The first full text NDT Journal on www.ndt.net, the Online Journal of Nondestructive Testing Ultrasonics, is on the Internet and each month provides new information as well as a comprehensive overall reference - access is free since it is sponsored by the NDT online exhibition. 

While professional awareness has increased, there are still hindrances to universal access in the workplace. Today almost all companies have access to the Internet, but company policy may limit usage during business hours or on company equipment Also, many countries still face prohibitive online access charges, although free market competition will take care of that in time, and Canada s no-charge policy may well be the wave of the future ... 

The Internet provides numerous powerful communication and multi-media tools, such as Inter Relay Chat (IRC), NetMeeting, White boards, Internet Phone, Archie, FTP, Telnet and many companies offer custom solutions with "plug-ins" But those are not the most important tools for access to information. The following outlines some of the "basics"... 

Once you have a website, there is another question how easy it will be to find your page on the Internet You will need Internet advertising to be visible on the Internet ... 

Some may say "We have invested in our own Internet presence (Home Page), so why we should advertise on the Internet Simply informing your established customers of your new Internet address is not sufficient. We ve already discussed some of the challenges users may face in searching for information. Your potential customer may lack the patience to follow hundreds of links of search engine output. 

The Internet advertising mechanism works much the same way as its "real world" counterpart. Company Homepages are electronic brochures and are disseminated by using new methods. But the methods are actually not new, they are basically the same as those used in printed journals This is efficiently done on an online Journal like NDTnet where advertising is concentrated in a virtual NDT Exhibition that attracts many readers to the site. The exhibitors have had good experiences with their presentations In contrast to individual Homepages which may often experience minimal traffic, NDTnet is visited by more than 6000 readers each month. Links to its exhibitors Homepages increase the audience and the information available. 

Bar-Cohen, R Diederichs, M Jones, M Onoe, International NDT technical Collaborations using the Internet. ASNT 1996 Fall Conference, http //www.ndt.net/article/www team/asnt-www.htm. 

Training and Certification Using Eddy-Current Simulators on the Internet. 

Edcfy-cufrent NDT inspections using spatial data (sampled scans) ha >e many benefits. They separate the two conflicting aspects of an inspection scanning and signal interpretation. An instrument/display (client/server) based NDT inspection based on sampled scan data aides in the training and certification of inspectors. It can be used over the Internet or in-house Intranet networks to train or examine inspectors at multiple or remote sites. This saves travel time and resources as defects, instrumentation and teaching can all be consolidated Samples can be maintained and distributed from a central certification body providing more control andflexibility. 

The second task is then analysing the results of the scan. The results can be displayed live on a display screen, or stored and presented all at once or after further scaling and analysis. This playback feature of sample data will be the subject of the remainder of the paper, for as we will see the playback need not be immediate nor on site, but could take place synchronously or asynchronously over the Internet. 

The instrument/display (client/server) paradigm allows for synchronous and asynchronous analysis, locally or remotely via the Internet or in-house Intranet network. 

The compact textual coding requires no graphical input and additionally permits a fast transmission. These are important advantages of using SMILES in chemical applications via the Internet and in online services. SMILES is also used for the input of structures in the Daylight Toolkit [22]. 

For all the different methods of chemical visualization, a lar e number of special techniques arc available, depending on the purpose of visualization. These software programs can be installed on a local computer or can be operated via the Internet. An ovemew of these programs is given in Section 2.12.3. 

To be able to access chemical information available on the Internet... 

Many biochemical databases with sophisticated topics have been developed for solving various problems. Since 1996 the first issue of each journal volume of Nucleic Acid Research has been reserved for the presentation of molecular biology databases [28]. A comprehensive catalog on the Internet is DBCAT, currently listing 511 databases [29, 30). 

Scientific, and especially chemical, information is becoming increasingly available on the Internet. This has the advantage that the information is accessible to other users. Additionally, the data formats (HTML, PDF, GIF, etc.) that are used are restricted to the most important ones to provide standards that are readable worldwide. Unfortunately, however, much of the information on the Internet is not reviewed or verified by other organizations as is the case in the primary literature. Thus, the quality of the information is extremely variable. 

Altogether, the Internet provides the following types of sdentific information ... 

The huge number of websites on the Internet (about 2,5 billion web pages December, 2002) containing chemical information is a great challenge when one is attempting to find specific information on a topic. Therefore numerous search engines have been developed and offered that provide fast access to the data. 

Given the enormous number of resources for chemical information available, many researchers do not have the time to learn the details of the variotis systems, and they end up searching in only a few resources with which they are familiar. This is a dangerous approach Knowing that both fee and non-fee resources are available on the Internet and both hold the desired information, it is prudent to search non-fee systems first and then use proprietary databases to fill data gaps [49]. 

All the methods of obtaining information via the Internet presented above carry one risk - dead links. Although a search term may be found by a search engine in its own website-metadata database, the original link to the website could be broken and the information is lost. In this book a conscious effort has been made to limit the URLs and to reduce the web address to the index page of the seiwer, to avoid this sometimes annoying problem. 

Infochcm s guide to chemistry software sources on the Internet http //www.chtmlslry-softwarc.exam/... 

Introduction Difficulties in Extracting Scientific Environmental Information from the Internet... 

Environmental information is available extensively on the free Internet. Two main reasons aeeount for this. First, the freedom of environmental information law and, secondly, the fact that many environmental databases which used to be available only commercially are now accessible on the free Internet. This section focuses on environmental information which is available free of charge on the Internet. Three main paths are distinguished for searching environmental information effectively. In general, all three routes should be taken into consideration for achieving a sound search result for environmental information on chemical stibstances... 

The word portal is often used for web sites that function as an entiy to a repo-sitoiy of information on almost any topic on the Internet. The following portal categories for chemical issues arc distinguished general chemistry sites substance information sites analytical chemistiy sites enviromnental chemistry sites toxicology and occupational health sites as well as patent seiwices [47],... 

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